About one-third of migraine patients who switched from galcanezumab to fremanezumab achieved a meaningful treatment response, regardless of whether the first drug worked.
71.4%of galcanezumab non-responders achieved a treatment response after switching to fremanezumab
What the researchers found
Among galcanezumab non-responders, 71.4% achieved a treatment response after switching to fremanezumab, demonstrating that response to one anti-CGRP antibody is independent of response to another.
Why it matters
Many migraine patients give up on CGRP antibodies after failing one. This study suggests switching to a different CGRP antibody — even one targeting the same molecule — can still provide relief, offering a simpler treatment step before changing drug classes entirely.
The numbers in context
The study tracked outcomes for patients switched between the two CGRP-targeting monoclonal antibodies.
How the study worked
Prospective registry-based cohort study at a single university hospital, tracking patients who received galcanezumab for at least 3 months before switching to fremanezumab for another 3+ months. Response was defined as a 50% or greater reduction in moderate-to-severe headache days.
Who was studied
Migraine patients switched from galcanezumab to fremanezumab after inadequate response
What this study cannot tell us
Very small sample size (21 patients) from a single center. No control group or blinding, so placebo effects and natural disease fluctuation cannot be ruled out. Only studied switching in one direction (galcanezumab to fremanezumab).
How to read the evidence
Moderate evidence: prospective registry data with clear outcome measures, but limited by small sample size, single center, and no control group.
When this study was published
Published in 2024. Reflects current CGRP antibody treatment landscape.
The bigger picture
CGRP-targeting monoclonal antibodies have transformed migraine prevention, but not every patient responds to the first one tried. This study adds to growing evidence that antibody switching within the same target class is a viable strategy, potentially delaying the need for entirely different treatment approaches.
Questions still open
- Would switching in the reverse direction (fremanezumab to galcanezumab) produce similar results?
- What biological mechanisms explain why patients respond differently to antibodies targeting the same molecule?
- Could patient characteristics predict who will benefit from switching versus changing drug classes?
Common questions
If one CGRP antibody did not work for my migraines, should I try another?
Are galcanezumab and fremanezumab the same thing?
Read the original research
Treatment Outcome After Switching From Galcanezumab to Fremanezumab in Patients With Migraine.
Journal of clinical neurology (Seoul, Korea), 20(3), 300-305
Citation
Youn, Michelle Sojung; Kim, Namoh; Lee, Mi Ji; Kim, Manho. (2024). Treatment Outcome After Switching From Galcanezumab to Fremanezumab in Patients With Migraine.. Journal of clinical neurology (Seoul, Korea), 20(3), 300-305. https://doi.org/10.3988/jcn.2023.0311